Here you see the cue ball in the mouth of a shot glass. The shot glass is frozen to the cushion. In the picture is the first diamond from the corner so you can see the shot glass is about one balls width away from it. The exact spacing will be determined by your shot glass. If you place the shot glass by the corner pocket with the mouth facing towards the long rail and roll it in an arc, that'll give you a decent starting point.

I use a level stroke, with mostly right english and a tip or so of top, obviously aimed toward the hanging ball in the far corner. If you shoot too hard, the shot glass will just roll end-over-end. Shoot too soft and it'll just plunk down and not roll. I'll leave it up to you to find the intermediate speed you need to make this shot.